Acute Myocardial Infarction (AMI), Thrombus Containing Lesion (TCL) and Saphenous Vein Graft Lesion (SVGL) are currently treated by techniques such as Percutaneous Transluminal Coronary Angioplasty (PTCA). Generally, Drug-eluting Stents (DESs), balloon catheters and Bare Metal Stents (BMSs) are used in PTCA. In addition, thrombus aspiration catheters are also used for treating TCL. The thrombus aspiration catheters retrieve a thrombus from a blood vessel and drain the thrombus out of a patient's blood stream.
Generally, polymers are used for loading the drugs onto the DESs. The polymers used in the DESs may lead to inflammation as a result of body's immune response to the polymers. Further, depending upon the properties of the polymers, the polymers used in the DESs may result in acute thrombus formation, sub-acute thrombus formation and late thrombus formation. The thrombus formed may further aggravate that may lead to blocking of the blood vessel thereby resulting in restenosis. Further, blocking of the blood vessel results in “slow-flow” and “no-flow” in patients suffering from AMI and TCL.
In addition to the DESs, the balloon catheters are also used for performing the PTCA for treating AMI, TCL and SVGL. However, the balloon catheters cause disruption of internal layers of the blood vessels and stretching of the blood vessels. The disruption of internal layers may lead to an acute thrombus formation, a sub-acute thrombus formation and a late thrombus formation. Whereas, the stretching of the blood vessel may result in inflammation. Further, stretching and the inflammation of the blood vessel may lead to restenosis. Thus, the sub-acute thrombus formation and the late thrombus formation may not be avoided when the balloon catheters are used.
Another insertable medical device used to perform PTCA for treating AMI, TCL and SVGL are the BMSs. However, the BMSs may also cause development of inflammation at the site of deployment as a result of body's immune response. The BMSs may rupture tissues of the blood vessels resulting in acute thrombus formation. The acute thrombus formation may further progress to a sub-acute thrombus and a late thrombus. Patients suffering from AMI, TCL and SVGL when treated with the DESs are observed to be more vulnerable to re-occurrence of lesions and thrombus as compared to patients treated with the BMSs and the balloon catheters.
Therefore, there is a need in the art for an improved drug-eluting insertable medical device for treating AMI, TCL and SVGL to overcome acute inflammation of the blood vessels resulting in thrombus formation. Further, in order to minimize the condition of “slow-flow” and “no-flow” of blood in patients suffering from AMI and TCL, an improved drug-eluting insertable medical device is needed in the art. Moreover, there is a need in the art for an improved drug-eluting insertable medical device to deliver an anti-inflammatory agent and an anti-thrombogenic agent without using polymers used for loading the drugs on the drug-eluting insertable medical device.